LOS ANGELES - "Jersey Boys" has become a global stage show triumph, but Clint Eastwood's new film version highlights the rivalries, shady dealings and hit records of 1960s megastars The Four Seasons.
The movie, based on the hit Broadway musical, shines a spotlight on what singer Frankie Valli and guitarist Tommy DeVito got up to when not cranking out top-10 singles like "Sherry" and "Oh, What a Night."
Based on a screenplay by Rick Elice and Marshall Brickman - co-author of Woody Allen's early movies - Eastwood follows the structure of the original musical, while not opting for a "Miserables"-style musical.
"Clint's career led up to the point where he could direct this movie," John Lloyd Young, who plays Valli and won one of four Tony awards bestowed on the Broadway show, said before the movie's US release Friday.
"Clint's been a jazz aficionado and musician his whole career, he scored some of his own movies, he knows music," he added.
"If you look at his career, there are these signposts along the way that say that when this show came along, he would be so well prepared to adapt it."
It was in the mid-50s that Valli and DeVito, two Italian Americans from New Jersey, formed their first group.
While Valli's falsetto voice brought them some attention, they had to wait until the 1960s and the arrival of Nick Massi and above all Bob Gaudio - who wrote all their songs - for The Four Seasons to take off internationally.
Songs like "Sherry," "Big Girls Don't Cry," "Walk Like a Man," "Rag Doll," "Save It For Me" and "Can't Take My Eyes Off You" became global hits.
But the group was finally brought down by internal jealousies and conflicts of interest, combined with DeVito's shady friends - the mafia is never far away - and financial mismanagement that forced Valli to underwrite its debts for several years.
And those divisions persisted.
"This is not a story from the past, this is a living, breathing story still going on," said Erich Bergen, who plays Gaudio.
"When we opened the show in Las Vegas, the original Four Seasons, those who are still with us, came out on stage and took a bow with us. Frankie wouldn't talk to Tommy. This story has not ended." Three of the film's four main actors worked on the Las Vegas stage production.
Newcomer Vincent Piazza (from TV show "Boardwalk Empire," and who plays DeVito), had never danced or sung on screen before.
But it wasn't a problem.
"Tommy wasn't the most adept or keen on just a group, he had a life outside of it," the actor told reporters.
"So if I'm off a step here or there, there is a certain bit of forgiveness, because he's the guy that would miss a step, that would be distracted by the things, whether be gambling, stealing money, women, that kind of thing."
Michael Lomenda, who had played Massi more than 1,200 times on stage, said the film "was a totally new experience because you have to figure out who you are as a group, you have the chance to develop your own identity."
Eastwood finished filming ahead of time and on budget as usual, shooting only one or two takes per scene and placing his full trust in his actors.
"Warner Bros has sort of handed the keys to the studio to him, at this point," said Bergen. "And he gets to a point in his career where he can do whatever he wants.
"There are very few people who could get a way with doing 'Jersey Boys' the way it (is) done, without putting stars in, or names I shoud say, without turning it into a Hairspray-type of glossy musical."